Hand operated sharpening device



April 13, 1954 EHRSAM 2,674,834

HAND OPERATED SHARPENING DEVICE I Filed Oct. 15, 1952 2 Sheets-Sheet lFIGJ- Hederialffihrsam,

Zmventor:

April 13, 1954 F EHRSAM 2,674,834

HAND OPERATED SHARPENING DEVICE Filed 001:. 15, 1952 2 $heets-Sheet 2 a.l a EEEM E m m R E 2% a m m m a \n m E W 9 N 1 w! A I; Healer umw naw.

C E E Z E C 18 Patented Apr. 13, 195 4 UNITED STATES ATENT OFFICE.

HAND OPERATED SHARPENING DEVICE Frederick Ehrsam, Oley, Pa.

Application October 15, 1952, Serial No. 314,877

10 Claims.

s invention relatestostone-lih h nd. held and manipulated sharpening orhonin dev ces, used for sharpening the. cutting ed es of articl s suchas knives, axes, machetes, scythes,s ickles, cutters, etc., andmoreparticularly concerns a device of this type provided with speci lhandle means so that the device may be safely and eificientlymanipulated for best sharpening. and other results.

One object of the invention is to provide a novel device of the type,indicated.

Another object is to provide such a device which has certainstructuraland functional features of advantage over the similar priorart devices.

Another object is to provide. such a device having means for protectingthe fingers of the user against accidental contact with the cutting edgebeing sharpened with the device.

It is also an object to provide such a device with-novel handle meansadapted to permit finger protected holding of the -device while carryingout the sharpening procedure in the most emcient manner.

A further object is to provide such a device having handle means adaptedto readily permit convenient immersionof the device in a cleaning fluid,when desired, so that the entire working surface or surfaces thereof maybe kept in condition for best sharpening results.

An additional object is to provide such a device having handle meansadapted to permit the device to rotate ormove in such manner during thesharpening operation as to effect uniform wear action of the device.

With these and other objects in view, which will become more readilyapparent'from the following detailed description of the practical andillustrative embodiments of my device shown in the accompanyingdrawings, the invention comprises the novel implement, the constituentelements thereof, features of construction and arrangement of parts incooperative relationship, as more particularly defined by the heretoappended claims.

In the accompanying drawings:

Figure 1 is a partial-perspective and partial sectional view of one formof my sharpening device, or implement, as it appears when held by thehand during the sharpening-of an edge of a'cutting blade.

Fig. 1A illustrates, on an enlarged scale, three exemplarycross-sectional configurations of typical cutting edges that maybesharpened with my novel device.

Fig. 2 is a front elevational view of the device shown in Fig. 1.

Fig. 3 is a rear elevational view of the device shown n Fig. ,1.

Fig. 4 is aside elcv-ational view of the device shown in Fig. 1.

Fig. 5 is a perspective View, similar to Fig. 1, but of a modified formof my sharpening device.

Fig. 6 is a vertical cross-sectional view of the device shown in Fig. 5,taken as indicated by the arrows 6- 5 on Fig. 7.

Figs. 7 and 8 are, respectively, front and rear elevational views ofthemodified form of my device shown in Fig. 5.

Fig. 9 is a cross-sectional view of a modified form of the device.

It will be helpful to an understanding ofmy invention to first brieflyconsider some of the more important aspects and phases thereof, so thatthese may be kept in mind during the subsequent reading of they detaileddescription of the practical and illustrative embodiments of my noveldevice as disclosed in the accompanyi drawings.

In general, when sharpening an implement with my novel device, such as amachete, axe, scythe, sickle, knife, etc, the bladeof the implement isheld in such manner that it faces the operator. This is done so that theoperator can observe the cutting edge of the implement at all times andnote the progress he is making during the sharpening operation. It iswell-known that a cutting edge is not sharpened to the fullest extent aslong as light is reflectedfrom it. By holding my novel device with theright hand in the manner indicated by Figs. 1 and 5, the operator canclearly observe both the cutting edge of the implement and the effect ofthe sharpening action thereon.

My novel device can also be utilized for re moving burrs from dies, inthe same finger protected manner as when sharpening implements, and forother purposes.

The special handle means of my novel sharpening device comprises anelongated flexible cordlike or chain-like element that is formed so thatit can be hooked or wound around one or more fingers, as desired, andfound most convenient by the operator, for the purpose of more or lessfirmly drawing the rear of the device against certain fingers and insuch manner as to permit the device to have a certain amount ofrotational freedom, whereby to effect uniform wear action thereof.

One form of my novel device is provided at the rear thereof with afinger tip protecting recess (see Figs. 1, 3 and 4) to permit the tipsof three fingers of the operators hand to be placed therein so as toguard or protect them against accidental contact with the cutting edgeof an implement while it is being sharpened. While so held thestone-like sharpening member'of the device may have more or lesspressure applied thereto by the fingers so as to permit rotationalmovement, as desired, for effecting uniform wear of the sharpeningsurface.

Another form of my novel device is provided device overhangs the ends ofthe fingers in order to keep the cutting edge that is being sharpenedfrom accidentally coming in contact with the fingers.

As hereinafter explained, my device may also be provided with a coarsegrained working surface and a fine grained working surface (see Figs.-8) so that it may be utilized to first rough grind and then finish honea cutting edge.

In Figs. 1, 2, 3 and 4 of the drawings, my device is shown as comprisinga sharpening, or honing stone I, that is shaped of suitable material,such as single grain, vitrified pure alumina (corundum) and includes acylindrical body having a rounded edge 2, that surrounds a flat grindingsurface 3. The rear end of the cylindrical body of the sharpening stoneis recessed to form a cavity or pocket 5 therein. The latter has anoutwardly inclined side wall 5, so as to provide a convenient,comfortable and protected location for accommodating the front ends ofthe thumb and first two fingers of the operators hand, as clearly shownin Fig. l. Extending rearwardly and centrally from the grinding surface3 is a small pocket forming recess 6, that is connected by a centralaperture 1 with the pocket 4 formed in the rear section of the stone 2.A handle ele ment or member is provided for holding the stone 1, in theform of a looped flexible cord 9, that is arranged to extend through theaperture 1 and has an anchoring knot at one end thereof located withinthe pocket E5. As shown, the looped portion of the cord 9 extendsrearwardly beyond the pocket i.

,With the parts of my device so arranged, the ring finger of theoperators hand may be engaged in the loop 9 of the cord 9, to draw theknot Hi against a shoulder H formed at the rear of the pocket 6, so asto force the rear of the sharpening stone over the tip of the thumb,index finger, and middle finger of the operators hand thereby to firmlyseat the stone l on these fingers for con venient and easy manipulationthereby.

By referring to Fig. 1 it will be apparent that the sharpening stone I,when held as indicated, can be readily circularly gyrated, orreciprocated in a straight line, or otherwise moved, while held at theproper angle against the side of the cutting edge of a cuttingimplement, indicated by the letter C in Fig. l. The cutting edge of theimplement C is preferably held so that the cutting edge thereof facesthe operator. This will enable the latter to observe the effect of thesharpening action on the cutting edge of the implement C during thesharpening operation until the desired shape and sharpness of thecutting edge has been attained.

The modified form of my device shown in Figs. 5 to 8 inclusive,comprises a sharpening stone of substantially disc-shaped formationwhich consists of two fixedly united parts or sections [3 and it. Thesetwo parts or sections are respectively formed of a coarse and fine grainof material suitable for carrying out the coarse and fine sharpeningwork for which this composite stone is intended. For example, the largerpart or section I3 is formed of coarse grain more alumina (corundum) andthe smaller part [4 of fine grain pure alumina (corundum), the saidparts being fused together and vitrified. The section I3 is centrallyprovided with a pocket l5 which extends inwardly from its fiatsharpening surface l3, and the section [4 is provided with a similarcentral pocket 16 which extends inwardly from its sharpening surface HThe said pockets l5 and I6 are connected by an aperture i! of smallerdiameter than said pockets so as to provide ashoulder i8 at the innerend of the pocket 15 and a shoulder 9 at the inner end of the pocket Hi.

If desired, a washer like metallic insert 20 may be fixedly embeddedinthe grinding stone between the coarse grain section [3 and fine grainsection I, as illustrated in Fig. 9, thereby to provide shoulders I8 andl9 and an aperture ll extending from one pocket to the other.

In Fig. 6 there is shown a handle element for the sharpening stone whichcomprises a flexible metallic chain 2| that is adapted to freely passthrough the hole l1. At each of its ends the chain 2| is provided with asmall, substantially bell-shaped member 22 and 23 arranged to becomeanchored when respectively pulled into and seated in the pockets l5 andI6 so that their outwardly flaring end flanges engage or abut theshoulders l8 or l9.

By pulling the flexible chain 2| from one side of the sharpening stoneto the other, either one or the other of the members 22 or 23 allows theflexible chain to extend from the sharpening stone so as to provide ahandle element that can be wound around a finger, or otherwise held, sothat the rear of the grinding stone is against the thumb and indexfinger of the operator's hand, while the outer ends of these fingers areprotectively located within the outer edge of the stone, as illustratedin Fig. 5. When held in this manner, the sharpening stone can be freelymanipulated to carry out a sharpening operation involving a circulargyrating motion or a lengthwise reciprocating movement along the cuttingedge of the implement C1 of Fig. 5. During such sharpening operation thestone may also be permitted to partly rotate in connection with eachsharpening movement of the stone, so as to effect uniform wear action ofthe latter. By seating either one or the other of the bell-shapedmembers 22 or 23 in its respective anchoring position within the stone,the handle element or chain 21 can be utilized for properly holdingeither the stone section I3 or the stone section It in position foreiiecting a sharpening operation.

The modified form of my device illustrated in section in Fig. 9,comprises a flexible loop forming cord handle element 24 havinganchoring members 25 and 26 at each end thereof so that the sharpeningstone may be held and manipulated by the insertion of two fingers intothe loop and drawing the stone against the tip of the fingers,substantially as illustrated in Fig. 1.

Fig. 1A shows three basic types of cutting edges which can be quicklyand easily sharpened by means of my device. The rounded corner of thesharpening stone is used to sharpen the concave, or hollow ground sidesof the cutting edge illustrated at the left in this figure, while thefiat sharpening faces of the stone are utilized to sharpen either thestraight or the convex sides of the cutting edges illustratedrespectively in the middle and at the right in Fig. 1A.

It is to be understood that my device is not limited in its use to thesharpening of implements and that it can be used in substantially thesame manner as herein indicated for removing burrs from dies, and forother purposes, to attain similar results.

Of course, the improvements specifically shown and described can bechanged and modified in various ways without departing from theinvention herein disclosed, the scope of which is more particularlyindicated by the hereto appended claims.

I claim:

1. A hand operated sharpening device of the character describedcomprising in combination, a member provided with a flat working surfaceat each end thereof, an elongated flexible handle element, anchoringmeans at each end of said element, and means within said member arrangedto receive one or the other of said anchoring means so as to effectextension of the handle element beyond the member in opposite directionto the working surface selected for operation.

2. A hand operated sharpening device of the character describedcomprising in combination, a member provided with a flat working surfaceat each end thereof which surfaces differ from each other in thiersharpening characteristics. an elongated flexible handle element,anchoring means at each end of said element, and means within saidmember arranged to receive one or the other of said anchoring means soas to efiect extension of the handle element beyond the member inopposite direction to the working surface selected for operation.

3. A hand operated sharpening device of the character describedcomprising in combination, a member provided with a flat working surfaceat each end thereof which surface differ from each other in theirsharpening characteristics, an elongated flexible loop-forming handleelement, anchoring means at each end of said element, and means withinsaid member arranged to receive one or the other of said anchoring meansso as to effect extension of the handle element beyond the member inopposite direction to the working surface selected for operation.

4. A hand operated sharpening device of the character describedcomprising in combination, a substantially cylindrically shapedstone-like member provided with a fiat external working surface at oneend thereof an elongated flexible handle element, anchoring means at oneend of said element, and means on said member arranged to receive saidanchoring means so as to effect extension of the handle element beyondsaid member in opposite direction to said working surface.

5. A hand operated sharpening device of the character describedcomprising in combination, a substantially cylindrically shapedstone-like member provided with a flat external working surface at oneend thereof and a finger tip' receiving pocket at the other end thereof,an elongated fiexible handle element, anchoring means at one end of saidelement, and means on the member arranged to receive said anchoringmeans so as to effect extension of the handle element beyond saidstone-like member in opposite direction to said working surface.

6. A hand operated sharpening device of the character describedcomprising in combination, a substantially cylindrically shapedstone-like member provided with a fiat external working surface and acurved working surface at one end.

thereof, an elongated flexible handle element, anchoring means at oneend of said element, and means within the stone-like member arranged toreceive said anchoring means so as to effect extension of the handleelement rearwardly beyond said stone-dike member.

7. A hand operated sharpening device of the character describedcomprising in combination, a substantially cylindrically shapedstone-like member provided with a fiat external working surface at thefront thereof and a finger tip receiving pocket at the rear thereof, anelongated fiexible loop-forming handle element, anchoring means at oneend of said element, and means located within the stone-like member andarranged to receive said anchoring means so as to effect extension ofthe handle element rearwardly beyond said stone-like member.

8. A hand operated sharpening device of the character describedcomprising in combination, a substantially cylindrically shapedstone-like member provided with a flat and a curved working surface atthe front thereof and having a finger tip receiving pocket at the rearthereof, an elongated flexible loop-forming handle element, anchoringmeans at one end of said element, and means located within thecylindrical member and arranged to receive said anchoring means so as toeffect extension of the handle element rearwardly beyond said member.

9. A hand operated sharpening device of the character describedcomprising in combination, a cylindrically shaped stone-like memberformed to provide a fiat external working surface of coarse grainsharpening material at one end thereof and a fiat external workingsurface of fine grain sharpening material at the other end thereof, anelongated flexible handle element, anchoring means at each end of saidhandle element, and means located within the stone-like member andarranged to receive one or the other of said anchoring means so as toeffect selective extension of the handle element beyond the stone-likemember in a direction opposite to said coarse grain surface or said finegrain surface.

10. A hand operated sharpening device of the character describedcomprising in combination, a cylindrically shaped stone-like memberformed to provide a flat and a curved external working surface of coarsegrain sharpening material at one end thereof and a fiat and a curvedexternal working surface of fine grain sharpening material at the otherend thereof, an elongated flexible handle element, anchoring means ateach end of said handle element, and means located within the stone-likemember and arranged to receive one or the other of said anchoring meansso as to effect selective extension of the handle element beyond thestone-like member in a direction opposite to said coarse grain surfaceor said fine grain surface.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 524,828 Kampfe Aug. 21, 1894 970,939 Mihills Sept. 20, 19101,111,873 Tomek Sept. 29, 1914 1,440,411 Peterson Jan. 2, 1923 2,129,279Kinsman Sept. 6,1938

